Blaise A. Nemeth

Exaggerated Inflammatory Response After Use of Recombinant Bone Morphogenetic Protein in Recurrent Unicameral Bone Cysts

Background Recurrent unicameral bone cysts (UBCs) can result in significant morbidity during a childs physical and emotional development. Multiple treatment options are available and a review of the literature fails to clearly define the optimal treatment for UBCs. Recombinant bone morphogenetic protein (BMP) has been used with success in other disorders of poor bone formation. This manuscript is the first to report on the use of recombinant BMP in the treatment of UBCs. Methods Three patients with recurrent UBCs underwent revision surgery with recombinant BMP. Radiographic and medical review was performed and is reported here. Results In these patients, the use of BMP failed to fully resolve their UBC; 2 patients had complete recurrence that required further surgery. In addition to poor radiographic results, all patients developed exaggerated inflammatory responses in the acute postoperative period. Each child developed clinically significant limb swelling and pain that mimicked infection. Conclusions On the basis of our poor radiographic results and a paradoxical clinical result, we no longer recommend the use of recombinant BMP in the manner reported here for the treatment of recurrent UBCs. Level of Evidence Level IV, case series.

Early treatment of scoliosis with growing rods in children with severe spinal muscular atrophy: a preliminary report.

Background Spinal muscle atrophy (SMA) is a progressive neuromuscular disease predominantly presenting in infancy and early childhood. Scoliosis is the most common spinal deformity in these patients and treatment in SMA patients is controversial. Treatment is usually definitive fusion. The purpose of this study is to evaluate a novel growing rod technique used to treat more involved children with SMA types I and II with scoliosis at an earlier age. Methods An Institutional Review Board approved retrospective medical record review was performed of children with SMA who were treated for scoliosis with the growing rod construct. Chart and radiographic data were reviewed. Eleven patients met the inclusion criteria, 4 male and 7 female patients. No patients were lost to follow-up. Mean follow-up was 43 months (range, 24 to 76 mo). The average age at time of surgery was 6 years. Five patients had a diagnosis of SMA I, 6 patients with SMA II. The 11 children underwent 45 surgical procedures, 12 growing rod implantations with 34 lengthenings. Technique: 4.5 mm titanium rods (Medronic Memphis, TN) were implanted obtaining a stable anchor point proximally with 4 pedicle screws and a cross link, and distally with 2 iliac bolts and 2 pedicle screws. Fusion is obtained at both anchor points by decortications and the use of bone graft. Subcutaneous low profile rods span between both anchor points using axial connectors. Results The average preoperative Cobb angle measurement of the major curve was 51.5 degrees (range, 38 to 76 degrees), postoperatively, 21.6 degrees (range, 2 to 34 degrees), and follow-up 18.7 degrees (range, 5 to 34 degrees). No surgical complications were identified or unplanned return to surgery. Medical complications were seen in 2 patients for postoperative pneumonia and anemia. Conclusions Growing rod construct is an effective option in the treatment of scoliosis in SMA patients with scoliosis. Level of Evidence Level IV (retrospective study).

Submaximal Treadmill Test Predicts V̇O2max in Overweight Children

OBJECTIVE To demonstrate the ability of a submaximal test to predict VO(2max) in overweight children. STUDY DESIGN A total of 130 children, 11 to 14 years old, with body mass index >85 percentile for age and sex performed a submaximal walking test. VO(2max) was measured by using open circuit spirometry during a graded exercise test to volitional fatigue. An equation to predict VO(2max) was modeled by using the variables of sex, weight (kg), height (cm), heart rate (HR) after 4 minutes during the submaximal test (4minHR), HR difference (4minHR - resting HR), and submaximal treadmill speed (miles per hour [mph]) in 75% of the subjects. Validation was performed by using the remaining 25% of subjects. RESULTS A total of 113 subjects achieved a maximal effort and was used in the statistical analysis. Development and validation groups were similar in all aspects. On validation, the mean square error was 241.06 with the predicted VO(2max) within 10% of the observed value in 67% of subjects. CONCLUSION VO(2max) was accurately predicted in this cohort of overweight children by using a submaximal, treadmill-based testing protocol.

The Diagnosis and Management of Common Childhood Orthopedic Disorders

Musculoskeletal illness represents a significant portion of office visits to primary care physicians. Despite this, little emphasis is placed on learning pediatric orthopedics during medical school or residency. Many articles have been written on selected disorders, or approaches to common conditions, such as the limping child. Sometimes determining where to start and how to move toward a diagnosis prevents prompt evaluation, referral, and treatment. Based on the authors experience as a general pediatrician trained in, and exclusively practicing, nonoperative pediatric orthopedics, approaches to selected complaints related to the musculoskeletal system are presented. Emphasis is placed on conditions resulting in frequent consultation with pediatric orthopedists from pediatricians and other primary care practitioners, either in the office or over the phone. Important features that may not be familiar to the primary care physician are highlighted, including the identification of aspects that require further evaluation and indications for consultation. Guidance regarding in-office management is also provided.

Pain management in patients with adolescent idiopathic scoliosis undergoing posterior spinal fusion: combined intrathecal morphine and continuous epidural versus PCA.

Study Design: A retrospective case-comparison study. Objective: Compare efficacy and safety of combined intrathecal morphine (ITM) and epidural analgesia (EPI) to that of conventional intravenous patient-controlled analgesia (IV-PCA) after posterior spinal fusion (PSF) for adolescent idiopathic scoliosis (AIS). Summary of Background Data: Pain control after PSF in AIS has been managed traditionally with IV-PCA. More recently studies have shown improvement in pain control with the use of continuous EPI or intraoperative ITM. No studies to our knowledge have compared the use of both ITM and EPI analgesia to that of IV-PCA. Methods: An Institutional Review Board-approved retrospective case-comparison study was performed from 1989 to 2009 of all patients undergoing PSF for AIS. Patients received either IV-PCA or ITM/EPI. Daily pain scores were recorded along with total opioid and benzodiazepine use. Adverse events were recorded for all the patients. Results: A total of 146 patients were initially included in the study; 95 patients received ITM/EPI and 51 received IV-PCA as a historical control. Eight patients from the ITM/EPI group were excluded from the pain comparison portion of the study. There were no statistical differences in age, sex, weight, or hospital stay between the 2 groups. The ITM/EPI group had, on average, 1 additional level of fusion (P=0.001). Daily average pain scores were lower in the ITM/EPI group on all hospital days, and statistically lower in days 1 and 3 to 5. Total opioid requirement was significantly lower in the ITM/EPI patients, although oral opioid use was higher among this group. Total benzodiazepine use was lower among the IV-PCA group. A total of 15.7% of the IV-PCA patients had bladder hypotonia, compared with 1.1% of the ITM/EPI group (P=0.002). The rate of illeus was 15.7% in the IV-PCA patients and 5.7% in the ITM/EPI (P=0.071). Respiratory depression was reported in 4 ITM/EPI patients, 0 in our PCA group. Technical catheter malfunction was reported in 8.5% of the EPI group. Conclusions: The use of ITM/EPI after PSF for AIS is safe and effective, this methodology provided significantly lower pain scores and lowers total opioid use which can lead to urinary and bowel dysfunction.

Developmental Dysplasia of the Hip

1. Blaise A. Nemeth, MD, MS* 2. Vinay Narotam, MD† 1. *Associate Professor, Department of Orthopedics and Rehabilitation, University of Wisconsin School of Medicine and Public Health, Madison, WI. 2. †Assistant Professor, Department of Orthopaedics, University of North Carolina School of Medicine, Chapel Hill, NC. * Abbreviations: AVN: : avascular necrosis DDH: : developmental dysplasia of the hip Early detection of developmental dysplasia of the hip is essential because restoration of the normal relationship of the femoral head and acetabulum increases the likelihood of normal development. Pediatricians must be aware of the American Academy of Pediatrics guidelines for early detection. After completing this article, readers should be able to: 1. Acknowledge the spectrum of hip pathology included in developmental dysplasia of the hip (DDH). 2. Identify newborns at risk for DDH. 3. Diagnose hip dislocations by using appropriate physical examination maneuvers. 4. Appropriately use imaging modalities to screen for DDH in infants who have normal or equivocal physical findings. 5. Recognize the presentation of hip dislocation in the older child. Developmental dysplasia of the hip (DDH) encompasses the spectrum of hip abnormalities involving the relationship between the femoral head and the acetabulum during early growth and development. A hip may be dislocated at rest, dislocatable (but in a normal position at rest), subluxed (incomplete contact between the femoral head and acetabulum), subluxable (incomplete contact induced with provocative maneuvers), or appear normal on physical examination yet have an abnormally shaped acetabulum or femoral head radiographically. The previously used term, “congenital hip dislocation,” has been abandoned in recognition of this spectrum, acknowledging as well the fact that a child may have normal examination findings at birth but progress to dislocation later in life. Strictly speaking, the term DDH does not apply to abnormal development of the hip due to other diseases, such as cerebral palsy, Legg-Calve-Perthes disease, or slipped capital femoral epiphysis, in which “hip dysplasia” is a sufficient term, nor does the term include traumatic dislocation. In addition, the term “teratologic dislocation” is reserved …

Cast-Saw Injuries: Assessing Blade-to-Skin Contact During Cast Removal: Does Experience or Education Matter?

Abstract Background: Cast-saw injuries are sustained during cast removal or splitting of a cast when a hot cast-saw blade touches the patients skin inadvertently during cast removal. Other studies have evaluated risk factors associated with saw-blade temperature, however, none have documented the number and duration of blade-to-skin contacts during cast removal. Methods: Using a pediatric long-arm model capable of detecting cast-saw blade contact, we tested the ability of health care providers to apply and remove casts before and after a brief education module. The total number and duration of “touches” between the saw and the models “skin” were recorded. Correlations between user “touches,” and experience and comparisons between pre- and post-education “touches” were performed. Results: Of the 18 study participants, 16 touched the model surface with the cast saw; 7 of the 18 participants maintained blade contact with the skin for > 1 second 22 times during the testing process. Participants with less experience averaged 20 (± 16) touches, whereas more experienced participants averaged 24 (± 19) touches (P = 0.7). Average number of touches was similar—before 22 (± 20) and after 25 (± 22); P = 0.5—participants completed an education module. No correlation between experience or participation in the education program was found with decreased number of blade-to-skin touches. Conclusion: Nearly all clinicians inadvertently contacted the underlying skin with the cast-saw blade. In our limited sample size, experience and education did not prevent this; therefore, minimizing time of contact and blade temperature may be more important factors in minimizing cast-saw injuries.

Magnetic Resonance Imaging of the Pediatric Knee

In pediatric patients, the high resolution and excellent soft-tissue contrast of magnetic resonance (MR) imaging allows for complete evaluation of osseous and soft-tissue structures around the knee joint, and its lack of ionizing radiation makes it a preferred modality for advanced imaging. Older children and adolescents are most commonly imaged to evaluate athletic and traumatic injuries, whereas in infants and school age children MR imaging is used to evaluate developmental conditions such as Blount disease or assess for causes of atraumatic pain such as infection or inflammatory arthritis. A thorough understanding of normal skeletal development is necessary to avoid misdiagnoses.

Osteonecrosis of the distal tibia metaphysis after a Salter-Harris I injury: a case report.

Posttraumatic osteonecrosis has been well described as a common phenomenon seen in fractures of the femoral neck, talus, and scaphoid. In the following case, we describe posttraumatic osteonecrosis in a rare location: the distal tibia. Our report details a child who sustained a distal tibia physeal injury and subsequently developed radiographic findings consistent with aseptic necrosis. Besides a traumatic incident, the patient did not have any of the risk factors known to cause osteonecrosis. Awareness of this complication after Salter-Harris I fractures will help reduce time to diagnosis and optimize treatment.

Can Radiographs Predict Outcome in Patients With Idiopathic Clubfeet Treated With the Ponseti Method

Background: The aim of this study was to determine if radiographic measurements, taken before tenotomy, can predict outcome in children with idiopathic clubfoot treated by the Ponseti method. Methods: A retrospective chart and radiographic review was performed on children with idiopathic clubfoot treated with the Ponseti method over a 10-year period with minimum 2-year follow-up that had a forced dorsiflexion lateral foot radiograph before tenotomy. All angles were measured in duplicate on the pretenotomy radiographs, including: foot dorsiflexion (defined as the 90 minus the angle between the tibial shaft and a plastic plate used to dorsiflex the foot), tibio-calcaneal, talo-calcaneal, and talo-first metatarsal angles. Clinical review of patient records identified different patient outcomes: no additional treatment required, relapse (additional casting and/or surgery required), recurrence (any additional surgery required), or reconstruction (surgery not including repeat tenotomy). Results: Forty-five patients (71 feet) were included in the study. The median age at follow-up was 4.6 years. The intrareader reliability was acceptable for all measures. Thirteen of the 71 (18%) feet required additional surgery, occurring at a median age of 3.6 years. Of the 4 radiographic measures, only pretenotomy foot dorsiflexion predicted recurrence (hazard ratio=0.96, P=0.03). Youden’s method identified 16.6 degrees of dorsiflexion as the optimal cutoff. Feet with at least that amount of dorsiflexion pretenotomy (n=21) experienced no recurrences; feet with less than that amount of dorsiflexion (n=50) experienced 13 recurrences (P=0.007). Conclusions: Reduced foot dorsiflexion on lateral forced dorsiflexion pretenotomy radiograph was associated with an increased risk of recurrence. Radiographic dorsiflexion to 15 degrees past neutral before tenotomy appears to predict successful treatment via the Ponseti method. Level of Evidence: Level IV.